Pneumatic hammer for driving nails.



WQ E. uoLwELL. PN-BUMATIU HAMMER FOB DRIVING NAILS.

K l APPLICATION PILEDNOY. 36,11910. n 1,014,639, j ,Patented Jan. 16, 1912.,`

2 BHEETvS-BHEETL W. E. COLWELL. PNEUMATIO HAMMER PGB. DRIVING NAILS,

urmouron r'ILnn 11011.25, 1910.

PmnaY Jag. 16,1912. 2 SHEETS-SHEET 2.

,5&1 11 111 1 1 1 mv QQ 1 fia ' ments in PneumaticsHammers `forljDriying broadest conceptiomzis toco'mbinewitha pneumatic means for the -pur l ose of posh so that at the next blow of the hammer,

c na'il willbe driven.' 20

' i object is to economizeinsairfas much as pos'w-.

mal position --native' ,formozffm'y invention.y y .Fignrel 1s a perSPeQtVeyew offm tool l pneumatic hammers fondrivmg nails ,i 'and In,A the alternative ;form, lof-` my"4 i!Wentiffiliy A the nai s being 1 remeyedg;

tionfo f'myppreferre fo ED STATES EvANs co'riwnrm,v cumino, emana.

WELL,` a subject; ofthe QfGreatBrit" ain residing 'at- Kincardme, 1n the county' of l3ruce,l Prox'rinceiofOntario, Canada,have invented certain Vnewjand usefulImprove-4y Nails, of which the following'isia specifica#- tion.` v i My invention relates "to improvements y1n one of the objects' of my invention, 1n its hammer driven Aoutward funder` the eontrolv of va motive Huid, preferably compressed air',

tioning thenail in` 'the' point-10 the :hammer In my `preferred formi, of

pressure-j A lllurther, objects of I nyinvention ill f ap.- pear in the' following! specificatioliz.. herein I describe,mypreferredform,and`f the- Slide valve is vifted "in pt is'itfiony inwthis yfgllclfgr -Of the alternative form pmyftol whe held?- `in-horiz0nta1 position, and Figi' 13de@ largedfcross section Aonthe line g-fh; toshovv the .constructionoi an alternative form 'fief @heefindcte correspendingl pants figure@ '1 A Th w01 herein desaibedas-Prticulrly designed t0 "beusedEbyI lathers, .inna-ili'ngl 01.1 y laths, it be. .f'thatf 001': 70 t'ain- Eartsfofv mytinvention eqnallf `plica 1e in connection with ariousc of r:mummia: tools,l Small-asy rock-drills.; Milly' cbnsidered, my. referred-fermaimvent'ion consists cfa, cyhnderdividediinta' two,Chambers-ene)ofthe Qhambrs signed; to `reoeive, the motiveinil to drivefntward theliairliner,r f amgf' 'berfin whichvthe" hammer roper operates, is l Whtiaetalmgaf .vacuum gember-assit does potcreeive any"otthemQwfPd i 1S$s0it Wthfthe-ylind, sb .fha 'han vuse P'Ylfhtlle 'lthnd "Sb, release thegchaml'ne an ef-,sametiplefo eratez'arv-valvecto each A als praetially-naealrlvthi "th f1 ames-pmi pressure Inithedrawmgs, like character-so e5 '-sitionjindicated at` the time the'tool is used y `mer to normal position.

i ing .wall E. Preferably 'screwed'over the Y,

so that it will/be positioned lin the head of" the tool; as the' hammer is moved backfto normal position.v The head of the hammer is constructed so as to permit the free entry.

of air intol they forward portion of the vacu`r um chamber in order to The cylinder A is composed of two suections B and C which screw into the bored casting D, which isprovided with the dividouter end ofthe section C ofthe 'cylinderv ,is thehead F. The section `B. screws into the casting K which carries the air-chest L suit;

' 'ably attached thereto." 4The dividingl'wall E separates the cylinder A'into a power chamber M and a vacuum chamber N.

is the hammer which operates within va formingr part of the-top plate b of the' the vacuum. chamber N, vand the inner en'd of this 'hammer isprovided with a piston V is aftrlp-rodhaving kbearing in theears castin D.. This trip rod has alsol bearing in its ront end inthe ear c carried by the section C. The trip-rod V passes'through the stuffing' box W` hel .-'in' the air chest L,

' and the housed end Xt ereof is bent to'enleading into the` power chamber- M, thus' introducing the motive fluid into this cham-l gage with a pocket Y formed infthe slide valve T., The motive Jfluid. is fed through i the coupling' d, and when they said trip-rod is moved inward in using the tool, the portv Uis brought into alinement with the port e 'ber behind the piston head S.

- lslot 3 formed 'in thejtrip-rod V..`

2 is a-.dog ope-rating i the' loilgapd'ihal .4' is a leaf-spring'secured-by the means shown, to the ltop plate b," the .free end of f which extends into a( ocketv formed in the .50

side of ,the dog 2.v his spring 4 `retains the dog 2 in the osition 'illustrated in Fig. 2.

ferate to 4withdraw e dog' 2 from the path 'lhe trip-'rod gis cutjawayasillustrated in F igs..1 ,and 2in. the vicinity' of the slot 3 so as to form cam surfaces' 'zagainst which operates the head '-.6 of the dog 2. This dogoperates'throughfa hole formed in the top plateb and also through the'casting Dland extends, through 'a hole in the section VC i downinto the vacuum,l chamber N so thatl .the annular Harige- 8 ofthe extension Q will -bfeheld by this dog and solock the hammer O in anormal. position. `lVhen 'i the trip-rod V is moved'inward 'to move `the slide valve T,"as before 'stated ,the cam surfaces 5 opof ymovement of the annular ange 8. The

movements of the parts'just'described are so adjusted that vfull pressureof the `motive fluid is being1 exertedV against the p iston n head S just before the dog 2 releases the hammer, and it .willl be understood that 'when thesaid dog is withdrawnsuflieiently,

the said hammer is shot forward vand-so l drives the nail, 9 held in the head.

,10 is a` port opening through the section B` and casting D, andthe position 'of vthis port is such that 'when the piston head S is moved to the limitof its out-movement, it

ymovesbeyond thesaid port, and allows the v Imotive Huidvto exhaust from' the power .the tool i's withdrawn from the lath 'or wall and by spring power, the trip-rod V is returnedy tonormal position thus' allowing the f dog 2 to be returned lto normal. iosition, and lcutting off the motive fluid' romthe air chest L. Now as my tool is constructed to practically. provide a vacuum in the chamber N between the piston fhead P and the dividing wall E, it will be understood that so soon as the said hammer has driven lthe nail, the atmospheric vpressure within the chamber N between` the head Aof the tool.

and the' piston head P willshoot the hammer back Vto normal position when it will be locked by the4 dog 2. One side of the dog 2 'is beveled as Vshown to to escape thereby.

permit the flange 8 v:

11 is any suitableshockfabsorbing. mate- 'rial carried bythe pistonod .R and 12 is aY stuing box throughw ich this piston' rod operates.

' 13 1s a port (see'llignriL particularly) which is normally closed by the spring valve 14 secured by the screw V 15 or other.- suitable means to the casting D." This spring-'valve 14 will ,preventany air escaping "into the vacuum, chambefN, and the functionof the v f same, together' with the port 13, is-to allow.'

the ready'. escape 'of any airthat may*l leak into'. the vacuum chamber so as' to reduce'to a mlnlmum an resistance oleredv to the' ini "movement of t e hammer O.l In order that cthis alternative'.form-of my device may work, `it will of course be understood that it'mustbe constructed soas to absolutely andthe piston-head' P. Should any air leak 1nto this chamber, during the in-movement l, prevent,yif possible, any escape ofair into@` i Lthe vacuum chamber- N between the wall'E ofthe hammerpO, the air will'be compressed bythe portl.,4

16 isfalslide valve carried .by the triprodV.

. yIn .order to prevent any` `back pressure piston-head Pand forced out of the I caused bythe com ression of fluid remain- 1n the power-c amber Ml after the firstv e l aust therefrom, I provide'a castin K s (see and 3)l withl a port 17 w 'ch 80 chamber M. So soon as thefnail 1s driven,

-rectl for this purpose.: In order 'to utilize.` k

l open. The tool is supposed .to .have been withdrawn from' the wall in Figs. 1, 2', 3,

[ `operation of' an alternative form 'ofmy and'5,l and therefore -as the said ports are open, anyv air remaining in the powerchams ber M is forced therefromby the return tonormal of the. hammer O without causing' any appreciable back pressure. `lllhen the trip Irod V is moved' by contact withv the" wall, the valve 16 closes' the ports 2 0 and 21- and 'so prevents theiescape of the `motive uid therethrough.,

` 7 'rod V, When this 'trip". rod is moved 'in- 20 vention.A Whereas in' the :preferred. fol'lllfl i the *hammer proper tonormal `position',l in

n coupled thereto as own' ati-76,j.is moved f so 'as to I brm'g.- the.v ort 77 intopalnement';

"when the motive :':The casting. K 'isprovided with .walls 72'and 73 s acedfapart so as tol formth airfchamber. 4. f The pipe-or couplin,gid` heldin `the [wall .73 andv conducts themotive .50;-

utilize the 'atmospheifiopressure to return this' alternative form I utilize the'motiyej lud'for this purpose. It is -oe'of theobf jects ofimy invention as embodied inthej alternative --form illustrated,v to utilize'i the 'full pressure of the'umotivefluid 'in returnaY ing the hammer to' normal i position without having to take airfrom e live pipe dil 1pressure of the motive fluid,l I must.` cient of this mot-ive fluid in the tool Huid from the live pipe' 1S l'. the' store su passing thereinto. z

shoved. inward v the cylinderrvalves with the ort l78. an -th'usallow"the motive fluid .un erA pressure to. esca elfrom the y air chamberv 74'" into-` said cy inder valve.

This` movement' of the said valvelalso brings the 'port 8o intoalinement with' the porn e1Y and Lallows motive luid tojrush' intothe power chamber `M and. sodriv'e .outward the "'hammer.' Oficourse'fat the Sametime thesaid orts are moving, 'means is operatedto he hammer, as' 'hereinafter de-- scribed. Wheithe piston:- head `S moves V65 beyond the port 10'-, the'- motivel Huid ei5i' A hausts from the' power chamber M int-o theA l scribed, the Hat-tened portion 84 will be motred intothe position shown in Fig. 11

to allow for theexhaust. The spring-22 returns the trip'rod V and cylinder valve .75 to normal position when `a nail has been driven, and as the port 77 communicates .with the port 7 8 after the port 80 has been moved out o f communication with the ,portv81, a full supplyl o'f motive fluidVY will beA stored in the cylinder valve 7 5 so that 'when the said/.spring "22 returns vthe. parts tonermal position,- the lport 85 formed in .the cylinder valve 75 will be in alinement with the port 86v opening through the casting D and the'section B', and will allow the motive `fluid from said cylinder valve and connected chambers to-"ru'sh into the powery chamber M' anddrive the piston heads and oon- "nected parts' back to normal position.

' The top plate vided'with a chamber 88 in which-'thercyl-- "ander valve 75 operates, and thisChamber communicates byl afport 89 formed in the df'. 92 is a plugmounted on said pipeand n screwing into the said sliding end. 93is a lset screw by means ofwhich the plug 92 can .bejheld in .adjusted position ontheipejuV 'By adjusting inward lor outward t e' position ofthe sliding end 91 the capacity of the .air-"chest can be regulated.

is a port formed in the casting K '.which' opens into the chamberlSf formed the? action lfof the stored'motive' uidfrom- .the-,cylinder valve 75, the valvel, has opened the port`17 inthe haust .t rough 'the port 10T," will `escape .throu h this valve intopthechamber 18 {outoy this. chamber -throu h the exhaust ,'pOrt'ZIJ" Of course whent e' trip rod;` Vf

city of this air chest *inthetop plate 87.116 is a valve whicl f operates in this' chamber 1 8. .When the f 1 piston` head S isbeing forced inward under'y vso that the mot-ive fluid ower chamberMthat did not ex-.

and

vided-:with an annular-Hangef .with which n 981s a leaf-spring suitably/"secured to the d to the dogy 96', `-which keeps The triprod V is( provided with a slot 3',

but in this form of my invention thev dog 2 Y is a pin 99 which screws' intol the dog 96,.l The head-100 of the pin 99 rests agalnst the yquirements of thev .of my cla'ims.

camsurfaces of they sides of the slot 3', as beforedescribed 4in connection wlth my preferred form of invention.

Vhile I have describedwhat I consider',

to be the best embodiments of my invention,

Ik desireit to be understood that vthe prin-y ciples can beembodied in' different form-s, and I desire' not to be' limited beyond the reprior art, `and the yterms nail-and said magnet. I do not confine myself to using this magnet, although, from l practice I have` found that when the tool is used in a vertical position. the magnet is lsome times useful; e. 9., if there is any diminution in the Ipressure of the motive liuid for the nail conduits. Should the pressure of the motive fluid fall too low, or the fluid be entirely cut off, the magnet will prevent the nail from dropping backinto the section C.- lBy providing4 the tongue of metal m,.I prevent the point 24 of the hammer from coming in contact with the magnet so that it will notv be magnetized.

- In my experiments I have found 4that' I can operate my hammer with the minimum pressure of -motive uid when the-:same is suddenly unlocked and shot forward under the'full pressure of the motive Huid. vIf the atmospheric-pressureshould be so great as to cause the hammer O to striketoo lgreat a blow agalnst the wall E, I provide an al- -ternative form of construction for the valve 14. The head 101 of the valve 14Lis provided I,with-a short conduit- 102 with which communicates a pipe 103 to -allow atmospheric air to rushv into the-vacuum cham' Aber when the hammer- O is driven outward.,

The plugV 104 screwinginto thel conduit 102. can be used to 'regulate the sup ly of air' into ,the pipe 103;- The supply of air through the parts just described Wi1l`,be quite small butv f 'will 'be vsufficient toy provideA 'a l cushion lfl compressed air Within vthe vacuum chamber to .largely absorb the shockdeveloped bythe 'return to normalof the hammer O." So asv l to absolutely insure the freeaction yof ,the

pry /sure of the atmosphere in' returning the h minerOto normal position, I -provide the sectlon .C lwlth a hole 2v. The constant stream i of compressed air passing through the cou- .pling -43 into the head "F-will' not,k interfere 'fwith the pressure' rough this hole.

lpassage-oit' air under atmospheric t.

What I claim -as my invention is:

1. A tool operatedy byv motive uid comprisingthe combination of a cylinder divided into a first and second chamber.; -a hammer operating in said second chamber, the outer end of which is open; a piston-rod attached to said hammer and operating in said lirst chamber; valve means for controlling the supply and lexhaust of motive Huid into and out of said first chamber; 'means for locking saidhammer 1n normal position, and. means whereby when the tool is pressed against a wall, said hammer is unlocked and said valve Y meansoperated to permit a supply of motive Huid to drive said hammer outward.

2. A tool operated by motive fluid ycornprising the combination of a cylinder divided intoa tirst and second' chamber; a hammer4 operating in said second chamber/theouter end of which is open;a piston-rod attached to said hammer and operating the said lsecond chamber; Ivalve means. for control@ ling the supply and exhaust of motive uid into'and out of said first chamber; means for locking said hammer in normal position,

and a trip-rod supported by -sai'd cylinder and normally yextending'beyond 'the front end thereof, and which, when pressed against a wall, will unlock'said hammer and operate said valve means' to permit a supply offmotiveiuid ,to drive said hammer outward. I y

3. A tool initially operated by motive Huid under pressure, comprising the combinationof a cylinder kdivided by a wall into a power chamber 'provided with intake and exhaust ports, and another chamber, Vthe front end of whichV is open; a'member .operating in.

said other chamber and provided with means to lit said chamber; a piston-rodwattached to saidFmemb'er vand operating' through-said`- W'all and in the said power chamber; valve Y means -for controlling the supply and exhaustof motive uid into'and out of lpower chamber, and-"means whereby when Vsaid member `and operating 4"through *said the tool is pressed'against a wall, said valvev means willbe operated to permit a supply of said motive fluid to drivesaid member outward, and to open said exhaust port, the'out-move.- lment of sa1d member causmg apartial vacuum inl said otherchamber' between said Wall and said member so thatl atmospheric pressure will return'said member back to ynormal postion. l' i 4. A tool initially operated `by motive fluid under pressure, vcomprising 'the combination of al cylinder' divided by ,'a wall into a power chamber provided with intake and exhaust f ports; and another chamber, the front end of whichjis open; a ymember operating said other chambe'rand provided, with means to fit said chamber; aI piston-rod attached to wall and in s 'aid power chambery; valve eans for controlling the 'supply' and exhaust of motive fluid into and out of saidl power chamber; means whereby when the tool is pressed against a wall said valve4 means will be operated to permit a supply of motive fluid to drive said member outward, andto opensaidexhaust port, Ithe out-moi-ement of said melnber causing a partial vacuum in said other chamber between said wall and said member so that atmospheric vpressure will return said member back to normal position, and a vvalve leading into said other chamber to control passage of air thereinto and therefrom, as and for the purpose specified. l

- 5. A tool initially operated byvmotive uid under pressure,lcomprising the combination of a cylinder divided by a wall into a power chamber provided with intake andexhaust ports, and another chamber, 'the front end of which is open; a member operating in said other chamber and provided with means to fit said chamber; a piston-rod attached to said member and operating through saidv` ,wall and in said power chamber; valve means for controlling the supply and ex- K haust of motive fluid into and out of said ,power chamber; means for lockin l said other chamber said member in normal position;means w ereby when the tool is pressed against a wall, said member will lbe unlocked, and Vsaid valve means operated to permit a supply of motive uid to drive said member'outward, and t0 open said exhaust port, the out-movement of a' partial vacuum in etween said wall and said member so that atmospheric pressure said member causing) win 'return said vmtmber back a, normal p0;

si'tion.l c

6. A tool initially operated by motive fluid under pressure, comprising the combination of a cylinder divided by a wall into a power p chamber provided with intake and exhaust ports, andi another chamber, the front' end of which 1s open; a member operating in said other chamberaldrovided with means t`o fit said chamber; a plston-rod attached to .said member and operating through saidl wall and in the power chamber; valve means for controlling the supply and exhaust of motive fluid into `and out of said ower chamber; means for lookin said mem er in'Y normal position; means w ereby whenthe tool ispressed against a wall, said member' will be unlocked, and said valve means voperated to permit a supply of motive Huid to drive said member outward, and to open said exhaust port, the out-movement of said member causing a partial vacuum In said otherfchamberlbetween said wall and said y r .WILLIAM EVANS coLwELL.

Witnesses: 4 i

' `R. M. I-ALL,

l S. C. TEACHER. 

